From what I remember when I was breeding them, there is roughly about a weeks or less between the babies free swimming and them spawning again. If you don't feed them extremely generously during those 2 weeks, the male will probably be too hungry to hold the eggs the entire time. I personally stole the eggs every other batch and tried to artificially incubate them in a tumbler because I was afraid he was getting too skinny.
Ming is spot on , if the male is to hungry he will eat the eggs. otherwise the male will spit the babys out 23 days after she gives him the egg sack. many times the lil guys are all hatched and just trapped in his mouth lol.If you can net him he will spit all the babys the second he is lifted from the water. thats how you can maximize you fry. just catch him on day 22 or 21.
if u want more to survive. hatch some brine and mix it with cyclops or daphnia for the first couple days. only the largest few of the newborn fry can eat frozen cyclops. but they grow fast. if you only feed them bbs they will die so u have to get them onto cyclops and daphnia asap.